1682684921 has 4 divisors (see below), whose sum is σ = 1697576052. Its totient is φ = 1667793792.

The previous prime is 1682684909. The next prime is 1682684953. The reversal of 1682684921 is 1294862861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1294862861 = 41 ⋅31582021.

It can be written as a sum of positive squares in 2 ways, for example, as 27415696 + 1655269225 = 5236^2 + 40685^2 .

It is a cyclic number.

It is not a de Polignac number, because 1682684921 - 2²² = 1678490617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1682684981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7445396 + ... + 7445621.

It is an arithmetic number, because the mean of its divisors is an integer number (424394013).

Almost surely, 2^1682684921 is an apocalyptic number.

It is an amenable number.

1682684921 is a deficient number, since it is larger than the sum of its proper divisors (14891131).

1682684921 is a wasteful number, since it uses less digits than its factorization.

1682684921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14891130.

The product of its digits is 331776, while the sum is 47.

The square root of 1682684921 is about 41020.5426707156. The cubic root of 1682684921 is about 1189.4173455811.

The spelling of 1682684921 in words is "one billion, six hundred eighty-two million, six hundred eighty-four thousand, nine hundred twenty-one".